How many sigma bonds and how many pi bonds are there in the tetracyanoethylene molecule

Mary is conducting an experiment on how pollution affects plant growth. how can she ensure that her data are reliable?

How does the atmosphere to make earth livable? check all that apply. causes the seasons contains oxygen provides warmth creates important nutrients blocks harmful energy from the sun plz like !

What is the molar mass of the anhydrous compound? answer using four significant figures. 36.02 g/mol 120.15 g/mol 156.12 g/mol